Neanderthals ‘had sex’ with modern man

Modern humans and Neanderthals had sex across the species barrier, according to a leading geneticist who is overseeing a project to compare their genomes.

Professor Svante Paabo, director of genetics at the renowned Max Planck Institute for Evolutionary Anthropology in Leipzig, will shortly publish his analysis of the entire Neanderthal genome, using DNA retrieved from fossils. He aims to compare it with the genomes of modern humans and chimpanzees to work out the ancestry of all three species.

I can’t say I’m surprised to see this. Later (transitional) Neanderthals picked up modern human traits like chins and more complex burial rituals, and a few sets of remains do look hybrid. If you look at the more recent reconstructions such as ‘Wilma’ (from Nat geo), they don’t look massively different to modern humans.

In addition to this there are numerous DNA studies that suggest a low level on Neanderthal contribution to Europeans (5% or less seems the norm) even though Neanderthal mitochondrial DNA and Y chromosomes are absent.

From looking at the difference between Mesolithic and modern Europeans mt DNA, I know that it would be easy to lose a small minority contributor through drift, and it’s unlikely that (as a group being exterminated) male Neanderthals would have made any kind of traceable contribution, as females may be absorbed from lower status groups, but males usually aren’t.

Theres also a vid which mentions the subject by Prof Paabo on the subject on Youtube. I guess we’ll just have to wait and see.

13 responses to “Neanderthals ‘had sex’ with modern man”

What does Paabo say in fact? That Neanderthals and humans probably had sex BUT that, even if they had offspring (what neither he nor I know), their genetic impact was virtually zero.

It’s funny how Paabo is the one who has smashed to the ground hybridation hypothesis and when he says that he believes that there was inter-species sex anyhow (but not effective descendants), his words are not just hyped by the media but by so many believers of the Neanderthal-Sapiens admixture hypothesis, last bastion of multirregionalism.

Sorry, but the facts are that Paabo and his team have several times smashed that belief already and are very likely to finally nail the hybridation hypothesis coffin next year when various full Neanderthal genomes should be available.

I’ve always thought it unlikely that they didn’t interbreed, which has inspired much opposition.

“know that it would be easy to lose a small minority contributor through drift”.

Not only drift. There have been any number of migrations into Europe since Neanderthals first encountered ‘modern’ humans. Each of these migrations would have further lowered the proportion of Neanderthal genes, so it’s not surprising that few traces are discernable.

What do you think about the National Geographic Genographic Project? Based on comments by Spencer Wells (head of the project) , one gets the feeling that they are making the data fit a particular conclusion.

The professor has been going on about the possibility of Neanderthal and AMH mating and having viable offspring for some time.

We know the genome of Chimpanzees and Humans, and we know how the two chromosome pairs of Chimpanzees fused to form the standard 23 pairs of humans. We also know that minute amounts of dna make all the variety of human types found today. It is probably safer to work on an extinct species of Homo than work on the actual differences in humans but logically it would be better to work with modern humans than with Neanderthals.

Other than curiosity I can’t see the point. Neanderthals are gone. Let them rest in peace.

I have a lot of doubts about the continuation of any humans in Europe prior to the Holocene/Neolithic Age. I have seen how humans who have stayed at the hunter gather stage of development, the Australian Aborigines, have handled contact with humans who have long past the Neolithic Age developments, Europeans and Asians. The Aborigines, the unmixed ones, have never taken up farming or the production and husbanding of plants and animals. The nearest they get to it is having large cattle ranches where the cattle are essentially wild, self sufficient. The Aborigines just round them up for sale. In Europe during the Neolithic Age, the Mesolithic human hangovers would have like Aborigines formed loose settlements near villages, living off scraps and discarded goods. The mixing would have been as happened in the modern era, between Neolithic men and the native women. The halfbreeds would gradually be absorbed by the farmers but at the lowest level until they would disappear as phenotypes into the farming community genomes. So if Europeans have any genetic admixture from humans who lived in Europe before the Neolithic, it was totally female. Another example of “Paleolithic” humans is the Andaman Islanders. They too, despite long contacts, if sporadic and hostile, have never become civilized preferring isolation and their hunting/gathering way of life.

Then Ponto wrote: ” I have a lot of doubts about the continuation of any humans in Europe prior to the Holocene/Neolithic Age”.

I think this adequately sums up why Neanderthal genetic contribution to modern humans is virtually, if not actually, nil. Doesn’t eliminate the possibility there was hybridism at about the same level as that between European and Australian Aborigine today.

It is worth noting that three of the links in the original post are different presentations of the same study.

The studies have very small sample sizes (a dozen and a score respectively) for detecting what would be a fairly small contributor to human ancestry, and they don’t say much about who is in the samples.

This matters because Neanderthal admixture had to have been with pre-Neolithic hunter-gatherers who were replaced/overwhelmed by Neolithic agriculturalists in recent times. So, if there was admixture, it should show more strongly in populations with a closer to to pre-Neolithic hunter-gatherers (perhaps Northern Finns, e.g.) than in Neolithic populations that would have had no further interaction with Neanderthals after their common ancestors became a source for pre-Neolithic hunter-gatherers who co-existed with Neanderthals in Europe. Put another way, the human race is not so homogenized that assumptions about independent, random interactions with Neanderthals by European modern humans collectively make sense. Without knowing the populations that sample individuals are drawn from, it is hard to know what model makes sense to use.

The study also doesn’t benefit from recent studies that show that the effective population of Neanderthals was very small, and the likelihood that the effective population of the incoming modern human population was significantly larger at the time that admixture could have happened (a conclusion that makes sense in light of the fact that modern humans eliminated megafauna, while Neanderthals didn’t pointing to greater hunting ability). The study also doesn’t address the likelihood that hybrids may have been at a reproductive disadvantage through sexual selection.

Finally, the study doesn’t show clearly how Neanderthal evolution into modern humans in Africa before modern humans left can be clearly distinguished from admixture afterwards, even if there is a genetic trace.

If you’ve study anything about evolution, biology, and fossils. You would know that nothing truly ever dies out. And as for humans, it is a funny story. Been around for tens of thousands of years, some humans have been isolated for about that long from current groups. No speciation ever taking place. It is a curious paradox. Any other group would have speciated any number of times already.

Some have speculated our species is really 300,000 years old or older and Neanderthal is really just a sub-species of humans.

Why is that such a hard thing to accept. “Well you need proof?” Able to create hybrids that in turn create more hybrids, what more proof do you need?

The difference between a Neanderthal and a Human is substantially less than there is between a Bengal and a Siberian Tiger.

I’m sure most of us (except, possibly, Maju) will share Mathilda’s sentiments, although perhaps not to the point of kissing you. It even made the local news on TV here tonight. From Chemmy’s link:

“The researchers estimated that the gene flow from Neanderthals to humans occurred between 50,000 and 80,000 years ago. The best explanation is that the admixture occurred when early humans left Africa and encountered Neanderthals for the first time”.

And that’s earlier than dates usually postulated for the magic OoA. Fits with the evidence for earlier presence in the levant though.